@@ -1476,22 +1476,7 @@ static void hv_balloon_ensure_mr(HvBalloon *balloon)
balloon->mr = g_new0(MemoryRegion, 1);
memory_region_init(balloon->mr, OBJECT(balloon), TYPE_HV_BALLOON,
memory_region_size(hostmem_mr));
-
- /*
- * The VM can indicate an alignment up to 32 GiB. Memory device core can
- * usually only handle/guarantee 1 GiB alignment. The user will have to
- * specify a larger maxmem eventually.
- *
- * The memory device core will warn the user in case maxmem might have to be
- * increased and will fail plugging the device if there is not sufficient
- * space after alignment.
- *
- * TODO: we could do the alignment ourselves in a slightly bigger region.
- * But this feels better, although the warning might be annoying. Maybe
- * we can optimize that in the future (e.g., with such a device on the
- * cmdline place/size the device memory region differently.
- */
- balloon->mr->align = MAX(32 * GiB, memory_region_get_alignment(hostmem_mr));
+ balloon->mr->align = memory_region_get_alignment(hostmem_mr);
}
static void hv_balloon_free_mr(HvBalloon *balloon)
@@ -1653,6 +1638,25 @@ static MemoryRegion *hv_balloon_md_get_memory_region(MemoryDeviceState *md,
return balloon->mr;
}
+static uint64_t hv_balloon_md_get_min_alignment(const MemoryDeviceState *md)
+{
+ /*
+ * The VM can indicate an alignment up to 32 GiB. Memory device core can
+ * usually only handle/guarantee 1 GiB alignment. The user will have to
+ * specify a larger maxmem eventually.
+ *
+ * The memory device core will warn the user in case maxmem might have to be
+ * increased and will fail plugging the device if there is not sufficient
+ * space after alignment.
+ *
+ * TODO: we could do the alignment ourselves in a slightly bigger region.
+ * But this feels better, although the warning might be annoying. Maybe
+ * we can optimize that in the future (e.g., with such a device on the
+ * cmdline place/size the device memory region differently.
+ */
+ return 32 * GiB;
+}
+
static void hv_balloon_md_fill_device_info(const MemoryDeviceState *md,
MemoryDeviceInfo *info)
{
@@ -1765,5 +1769,6 @@ static void hv_balloon_class_init(ObjectClass *klass, void *data)
mdc->get_memory_region = hv_balloon_md_get_memory_region;
mdc->decide_memslots = hv_balloon_decide_memslots;
mdc->get_memslots = hv_balloon_get_memslots;
+ mdc->get_min_alignment = hv_balloon_md_get_min_alignment;
mdc->fill_device_info = hv_balloon_md_fill_device_info;
}
Let's implement the get_min_alignment() callback for memory devices, and copy for the device memory region the alignment of the host memory region. This mimics what virtio-mem does, and allows for re-introducing proper alignment checks for the memory region size (where we don't care about additional device requirements) in memory device core. Signed-off-by: David Hildenbrand <david@redhat.com> --- hw/hyperv/hv-balloon.c | 37 +++++++++++++++++++++---------------- 1 file changed, 21 insertions(+), 16 deletions(-)